The novel circRNA circ_0045881 inhibits cell proliferation and invasion by targeting mir-214-3p in triple-negative breast cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer (BC). The circRNA-miRNA‒mRNA axis is a promising biomarker for the early diagnosis and prognosis of BC. However, the critical circRNA mediators involved in TNBC progression and the underlying regulatory mechanism involved remain largely unclear. METHODS: In this study, we carried out a circRNA microarray analysis of 6 TNBC patients and performed a gene ontology (GO) analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was used to characterize important circRNAs involved in TNBC progression. The interaction between circRNAs and miRNAs was determined by dual luciferase and RNA immunoprecipitation (RIP) assays. Moreover, Transwell, wound healing and Cell Counting Kit-8 (CCK8) assays were performed with altered circRNA or miRNA expression in MDA-MB-231 and BT-549 cells to investigate the roles of these genes in cell invasion, migration and proliferation. RESULTS: A total of 78 circRNAs were differentially expressed in TNBC tissues, and the hsa_circ_0045881 level was significantly decreased in TNBC tissues and cells. Lentivirus-mediated hsa_circ_0045881 overexpression in MDA-MB-231 and BT-549 cells significantly reduced cell invasion and migration capacity. Additionally, hsa_circ_0045881 interacted with miR-214-3p in MDA-MB-231 cells. miR-214-3p mimics in MDA-MB-231 and BT-549 cells significantly enhanced cell invasion, migration and proliferation, but the other combinations of inhibitors had opposite effects on cell activity. CONCLUSIONS: Our data indicated that the circRNA has_circ_0045881 plays key roles in TNBC progression and that hsa_circ_0045881 might act as a sponge for miR-214-3p to modulate its levels in TNBC cells, thereby regulating cell invasion, metastasis and proliferation. hsa_circ_004588 might be a potential prognostic marker and therapeutic target for TNBC.

CircRNA circSEPT9 Downregulates miR-10a through Methylation to Promote Cell Proliferation in Laryngeal Squamous Cell Carcinoma.

The oncogenic functions of circRNA circSEPT9 have been characterized in triple-negative breast cancer. We analyzed its role in laryngeal squamous cell carcinoma (LSCC). Quantitative reverse-transcription PCR (RT-qPCR) was used to analyze the expression of circSEPT9 and miR-10a in paired LSCC and nontumor tissues donated by 50 patients with LSCC. Methylation-specific PCR (MSP) was performed to analyze the role of circSEPT9 in miR-10a RNA gene methylation. circSEPT9 or miR-10a were overexpressed in LSCC cells to explore the interaction between them. The regulatory role of circSEPT9 and miR-10a in cell proliferation was studied with cell counting kit-8 (CCK-8) assay. CircSEPT9 was highly expressed in LSCC, whereas miR-10a was expressed at a lower level in LSCC. CircSEPT9 and miR-10a were closely correlated across LSCC tissue samples. In LSCC cells, circSEPT9 overexpression increased the methylation of the miR-10a gene and decreased the expression of miR-10a. CircSEPT9 overexpression increased LSCC cell proliferation, whereas miR-10a overexpression decreased cell proliferation. Co-transfection experiments showed that circSEPT9 overexpression attenuated the effects of miR-10a overexpression on cell proliferation. We conclude that circSEPT9 may increase miR-10a methylation to increase cell proliferation in LSCC.

P2Y2 promotes fibroblasts activation and skeletal muscle fibrosis through AKT, ERK, and PKC.

BACKGROUND: Skeletal muscle atrophy and fibrosis are pathological conditions that contribute to morbidity in numerous conditions including aging, cachexia, and denervation. Muscle atrophy is characterized as reduction of muscle fiber size and loss of muscle mass while muscle fibrosis is due to fibroblasts activation and excessive production of extracellular matrix. Purinergic receptor P2Y2 has been implicated in fibrosis. This study aims to elucidate the roles of P2Y2 in sleketal muscle atrophy and fibrosis. METHODS: Primary muscle fibroblasts were isolated from wild type and P2Y2 knockout (KO) mice and their proliferating and migrating abilities were assessed by CCK-8 and Transwell migration assays respectively. Fibroblasts were activated with TGF-ß1 and assessed by western blot of myofibroblast markers including α-SMA, CTGF, and collagen I. Muscle atrophy and fibrosis were induced by transection of distal sciatic nerve and assessed using Masson staining. RESULTS: P2Y2 KO fibroblasts proliferated and migrated significantly slower than WT fibroblasts with or without TGF-ß1.The proliferation and ECM production were enhanced by P2Y2 agonist PSB-1114 and inhibited by antagonist AR-C118925. TGF-ß1 induced fibrotic activation was abolished by P2Y2 ablation and inhibited by AKT, ERK, and PKC inhibitors. Ablation of P2Y2 reduced denervation induced muscle atrophy and fibrosis. CONCLUSIONS: P2Y2 is a promoter of skeletal muscle atrophy and activation of fibroblasts after muscle injury, which signaling through AKT, ERK and PKC. P2Y2 could be a potential intervention target after muscle injury.

Study on web pillar failure mechanism during auger mining and its associated risk assessment.

To safely and efficiently recover trapped coal under final endwalls in open cut mines, theoretical analysis and numerical calculation were used to study the stability of web pillar during auger mining. The partial ordered set (poset) evaluation model was used to develop a risk assessment methodology, and auger mining at Pingshuo Antaibao open cut coal mine was used as a field example for validation. Based on the catastrophe theory, the failure criterion of web pillar was established. From the limit equilibrium theory, the maximum allowable plastic yield zone width and minimum web pillar width were proposed under various Factor of Safety (FoS) thresholds. This in turn provides a new method for web pillar design. Based on the poset theory and combining with the risk evaluation and proposed hazard levels, input data were standardized and weighted. Subsequently, the comparison matrix, HASSE matrix and HASSE diagram were established. The study shows that: when the width of the plastic zone of web pillar exceeds 88% of the total width, web pillar may be unstable. Based on the calculation formula for the required width of web pillar, the required pillar width was 4.93 m and it was deemed as "mostly stable". This was consistent with the field condition on site. Such that this method was validated.

Changes in surface characteristics and adsorption properties of 2,4,6-trichlorophenol following Fenton-like aging of biochar.

Fenton-like system formed in a natural soil environment deemed to be significant in the aging process of biochar. Aged biochars have distinct physico-chemical and surface properties compared to non-aged biochar. The aged biochar proved to be useful soil amendment due to its improved elements contents and surface properties. The biochar aging process resulted in increased surface area and pore volume, as well as carbon and oxygen-containing functional groups (such as C=O, -COOH, O-C=O etc.) on its surface, which were also associated with the adsorption behavior of 2,4,6-trichlorophenol (2,4,6-TCP). The biochar aging increased the adsorption capacity of 2,4,6-TCP, which was maximum at pH 3.0. The 2,4,6-TCP adsorption capacity of aged-bush biochar (ABB) and aged-peanut shell biochar (APB) was increased by 1.0-11.0% and 7.4-38.8%, respectively compared with bush biochar (BB) and peanut shell biochar (PB) at the same initial concentration of 2,4,6-TCP. All biochars had similar 2,4,6-TCP desorption rates ranging from 33.2 to 73.3% at different sorption temperatures and times. The desorbed components were mainly 2,4,6-TCP and other degraded components, which were low in concentration with small molecule substance. The results indicated that the aged-biochar could be effective for the long-term remediation of naturally organic polluted soils.

Characteristics of organo-mineral complexes in contaminated soils with long-term biochar application.

Long-term studies on the environmental effects following biochar additions to soils, while plentiful, are predominantly focused on the soil fertility, whereas few are on the soil organo-mineral complexes. This study examines the changes of organo-mineral complexes in an acidic paddy soil and a saline-alkali soil which were remediated using biochar for approximately 8 years and 3 years, respectively. The results showed that loosely combined humus increased by 30.1% and 25.1% with the application of 40 t ha-1 biochar in the acidic paddy soil and the saline-alkali soil, respectively. Meanwhile, an increase of cement (Fe-oxides) was the contributor to the rise of the complexes content. Complex iron in the saline-alkali soil were 30% higher than in the acidic paddy soil with the application of 40 t ha-1 biochar. Fourier Transform Infrared Spectroscopy showed oxygen-containing functional groups on the surface of the biochar separated from the remediated field. X-ray diffraction analysis indicated that both complexation and sedimentation were involved in heavy metal immobilization. It was found that biochar amendment mitigated the effect of acid rain leaching and reduced vertical migration of the Fe/Al-bound complex, which can prevent soil from podzolization and thus improve its fertility.

Main branch of ACN-to-RLN for management of laryngospasm due to unilateral vocal cord paralysis.

OBJECTIVES/HYPOTHESIS: This study explored the feasibility and efficiency of main branch of ansa cervicalis nerve (ACN)-to-recurrent laryngeal nerve (RLN) anastomosis for management of paroxysmal laryngospasm due to unilateral vocal cord paralysis (UVCP). METHODS: Thirteen patients who underwent main branch of ACN-to-RLN anastomosis for management of paroxysmal laryngospasm due to UVCP were enrolled in the present study. Multidimensional assessments, including videostroboscopy, voice assessment, and laryngeal electromyography (LEMG), were performed preoperatively and postoperatively. RESULTS: This series was limited to UVCP with iatrogenic causes, including thyroidectomy, cervical spine surgery, and thoracic surgery. After main branch of ACN-to-RLN anastomosis, all cases showed significant airway improvement, and laryngospasm was completely abolished in 92.3% (12 of 13) of cases. Videostroboscopy showed that the bulging and paradoxical adduction of the affected vocal cord during a sniff were abolished immediately after operation, and there was no significant difference in vocal fold position or glottal closure before versus after the operation. LEMG showed that the postoperative recruitment and amplitude of voluntary motor unit potential in the affected thyroarytenoid muscle during a sniff were significantly decreased compared to preoperative values, and postoperative recruitment showed significant improvement during phonation compared to that preoperatively. Voice assessment showed that there were no significant differences in overall grade, roughness, breathiness, jitter (local), shimmer (local), noise-to-harmonics ratio, or maximum phonation time after the operation compared to the preoperative values. CONCLUSIONS: Main branch of ACN-to-RLN anastomosis could have long-lasting efficacy in the management of paroxysmal laryngospasm due to UVCP, with no apparent compromise of voice quality. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2412-2419, 2020.

Insights into the effects of long-term biochar loading on water-soluble organic matter in soil: Implications for the vertical co-migration of heavy metals.

Although interest in biochar remediation is growing, the effects of long-term biochar loading on soil environments have not been clearly confirmed. The contents and characteristics of water-soluble organic matter (WSOM) from soils after eight years of biochar remediation were investigated, and the vertical co-migration of heavy metals controlled by interactions between WSOM, soil and contaminants were also analyzed. The results showed that biochar-leaching WSOM featured high aromaticity. Fluorescence excitation-emission matrix (EEM) spectrophotometry was employed, and three primary components, including fulvic-acid-like (FA-like), tryptophan, and humic-acid-like (HA-like) compounds, were identified in the EEM spectra via parallel factor analysis models. With increasing biochar loading, FA-like and HA-like greatly increased, but tryptophan showed a weak response. Furthermore, the WSOM was freeze dried and analyzed with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, and the results demonstrated that the BC treatment increased oxygen-containing functional groups and enhanced the complexation capability of the WSOM. Finally, the Cd and Pb concentrations in the WSOM were investigated, and Cd was found to decrease in top-soil WSOM with added BC because of increased complexation, but the Pb content increased because exchangeable and carbonate Pb converted into organic Pb. Further, the Cd and Pb concentrations decreased in sub-soil WSOM. These findings suggest that more efforts should be devoted to studying the effects of long-term biochar loading on soil environments.

Effects of laboratory biotic aging on the characteristics of biochar and its water-soluble organic products.

Effects of biotic aging on the characteristics of biochar and its water-soluble organic products were determined through a one-year laboratory incubation study. Biochar had a positive influence on microbial population size. Without microbial addition, biochars showed little change, except for an obvious increase in oxygen content from 3.2% to 6.3% after one year. By contrast, the carbon (C) content of the biologically-aged biochars continually decreased throughout the incubation at two humidity levels, suggesting that microbes consumed biochar C or encouraged organic matter solubilization. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated that all aged biochar surfaces showed increases in oxygen-containing functional groups and TG-DTG analysis showed that biologically-aged biochars were less stable than the corresponding abiotically-aged one. The release of dissolved organic matters from biologically-aged biochar logarithmically increasing with time, corresponded with of the pattern of microbe production, suggesting microbial involvement in solubilizing biochar. Combined three-dimensional excitation-emission matrix (3DEEM) and parallel factor (PARAFAC) analyses revealed that fulvic and humic acid-like components were the main water-soluble products of biologically-aged biochar, and these became increasingly rich in O-containing functional groups, i.e. humified, over time. These results highlight the importance of microbes in chemically transforming biochar and the dissolved products of biochar during aging.

Effects of Wet Oxidation Process on Biochar Surface in Acid and Alkaline Soil Environments.

Biochar has been studied for remediation of heavy metal-contaminated soils by many researchers. When in external conditions, biochar in soils ages, which can transform its structural properties and adsorption capacity. This study was conducted with two oxidation processes, HNO3/H2SO4 and NaOH/H2O2, to simulate the effects of biochar in acid and alkaline soil conditions. The results show that the oxygen-containing functional groups increased in aged biochar, which led to improve the ratio of oxygen and carbon (O/C). Nitro functional groups were found in the acid-oxidation treated biochar. Destroyed ditches and scars were observed on the surface of aged biochar and resulted in growth in their specific surface area and porosity. Specific surface area increased by 21.1%, 164.9%, and 63.0% for reed-derived biochar treated with water washing, acid oxidation, and basic oxidation, respectively. Greater peaks in the Fourier Transform Infrared Spectroscopy (FTIR) results were found in C⁻O and O⁻H on the surface of field-aged biochar. Meanwhile, mappings of energy-dispersive spectroscopy showed that biochar aged in soil was abundant in minerals such as silicon, iron, aluminum, and magnesium. In summary, biochar subjected to wet oxidation aging had an increased capacity to immobilize Cd compared to unaged biochar, and the adsorption capacity of oxidized biochar increased by 28.4% and 13.15% compared to unaged biochar due to improvements in porosity and an increase in functional groups.

Effects of chemical oxidation on surface oxygen-containing functional groups and adsorption behavior of biochar.

Biochar is a beneficial soil amendment but the changes in its surface properties during the aging process, especially the oxygen-containing functional groups and the associated adsorption behaviors, are not well documented. In this paper, the aged wheat straw biochar was simulated by chemical oxidation with HNO3-H2SO4 and NaOH-H2O2 systems. Characterization results showed that carbon loss and oxygen incorporation ran throughout the aging process. Surface oxygen-containing functional groups were found to be increased in all treated biochars, especially for carboxyl. Much more developed mesopores were observed in aging biochar, specific surface area was increased by 126% for biochar treated with NaOH-H2O2, and 226% for biochar treated with 40% of HNO3-H2SO4. Thermogravimetric analysis showed that the increasing oxygen-containing functional groups led to 14% and 30% mass loss by treating biochar with alkali and acid, respectively. The improved biochar surface through the increase of oxygen-containing functional groups enhanced the cadmium sorption capacity, and the sorption capacity increased by 21.2% in maximum. Roughed surface from oxidation was another reason for increasing cadmium adsorption. Results indicated that the adsorption performance of biochar on pollutant would be changed during aging process along with the changing surface properties.